A driver in a hurry might find it challenging enough to absorb all the information in that sign. But then there's the top one, an older sign meant to clear the avenue for traffic during rush hours. That's a fine thing to do.

McIntire says that the District does indeed start ticketing and towing on the avenue after 4 p.m. on weekdays, something that will strike many commuters as good news. It's just that it bans parking during some of the afternoon time when the lower sign would seem to permit it.

The District Department of Transportation is aware of the problem and a work order has been issued to get some replacement signs reflecting the fact that parking is banned during the afternoon rush, just as the red and white sign declares, said John Lisle, a spokesman for the department.

What to do in the meantime, or if you encounter a similar conflict elsewhere?

"The best advice we can give anyone about parking, when there is an apparent conflict in the signage, is that you should always abide by the most restrictive sign," Lisle said. "For example, if one sign says you can park in a space during rush hour and another says you can't, you would be wise to find another place to park or you run the risk of getting a ticket."

From Dr. Gridlock: Redial1, I think the problem was that the District didn't make its signs in sufficient variety to account for all the parking rules. In our example, you wouldn't want them to take down the red and white sign at the top -- the one that warns of the rush-hour parking restrictions -- at the same time they put up the green and white one with the parking rules.

What you'd want, I think, is to have a green and white one that explained the parking rules while also accounting for the rush hour restriction. (And that's what DDOT says it's now going to put up.)

Well, you would also want the new parking payment machines to not sell permits for a time period where parking is illegal on that street. Whatever the green signs say, there would not be an issue if the vend-o-mats worked properly. Depriving people of the opportunity to pay for parking they cannot use, though, would be a bit "unaccomodating" (where "accomodating" has the perverse meaning Dr. Gridlock uses to describe changing evening and weekend parking from free to pay).

Just like red light cameras and speed traps, public safety isn't the primary purpose of DC street signs. They are there to raise revenue for the stunningly mismanaged (unmanaged) District. BTW, does anyone know the details of "Mayor" Fenty's schedule in the coming weeks?

Parking restrictions have nothing to do with the city raising revenues. These types of signs exist for one simple reason... drivers demand them. Examples:

1. People want to drive in the city and park whenever they want for however long they want, but then complain when there isn't enough on-street parking. Solution: Restrict the number of hours an individual may park.

2. Those same individuals complain that they need more than the 2 hours provided during the evening. Solution: Lift the hourly restriction at night.

3. Finally, the same people who demand to park whenever and wherever they want also want to have as many lanes of traffic flowing during rush hour. Solution: Restrict parking during rush hour.

It's hypocritical for drivers to complain about parking restrictions when it's they who demanded them in the first.